Effects of Ginkgo biloba extract on somatosensory evoked potential, nitricoxide levels in serum and brain tissue in rats with cerebral vasospasm after subarachnoid hemorrhage

This study aimed to investigate the protective effects of Ginkgo biloba ext ract on cerebral vasospasm and neural damage following subarachnoid hemorrh age (SAH) in rats. It was found that the regional cerebral blood flow decre ased immediately and persistently after SAH in SAH rats. The latency of som atosensory evoked potential delayed progressively. The nitric oxide levels in serum and brain tissue decreased and increased, respectively, after SAH. Ginkgo biloba extract effectively antagonized the changes of above paramet ers. It was concluded that somatosensory evoked potential is useful for the judgement of cerebral ischemic damage during cerebral vasospasm after SAH. Decrease in serum nitric oxide and increase in brain tissue nitric oxide a re important factors leading to cerebral vasospasm and neural damage, respe ctively, after SAH. Ginkgo biloba extract relieves cerebral vasospasm and c erebral ischemic damage by reversing the pathological alteration of nitric oxide.